## biebergeo 3 years ago find a b c d diagram attached!

1. biebergeo

|dw:1335311854394:dw|

Okay . . . . do you know if the four angles in the middle are all right angles?

3. biebergeo

|dw:1335312024131:dw|

4. biebergeo

no i don't kno it doesn't indicate

Okay

Does the problem give any other info., or is what you put up all they give you?

7. biebergeo

that is all it gave :( i can't figure it out.

Okay, I understand . . . don't worry

9. biebergeo

do you understand it?

One sec . . . I'm looking up a rule for this

11. biebergeo

okay thanks

Well, I thought that you might need to use the property for adjacent angles (with alternate interior, exterior, etc.), but I'm not sure if that would work, here. As I'm a bit rusty with this, let me see if I can get someone else on here, to help you . . . .

13. biebergeo

that sounds familiar maybe you are correct

Remember that the key thing here, is that triangles have 180 degrees

16. mubzz

For angles in the same segment, angle at centre is twice angle at the circumference. Therefore, b = 2*53 = 106 b and c are angles on a straight line and their sum should be 180, therefore c = 180-106 c= 74 for a, again use the same property used to find b, therefore a is also 53 Another property is that the angle subtended by the diameter (in this case it is the line that passes through centre and touches a b and c) is always 90. Therefore (d+53)=90 Answers: a = 53 b = 106 c = 74 d = 37

Ah . . . thanks mubzz!

18. biebergeo

THANK YOU!!!!!!!!!!!!!!!!!!!!!!!!!